Dreams of Daylighting
6 June 2011 |
A trio of urban dreamers—young Mexico City architects—have submitted a plan to uncover three of that city’s lost rivers (there once were 60 of them). “Imagine kids singing, playing in the water and dancing,” said one of the dreamers, Delfín Montañana, to New York Times writer Damien Cave in last Tuesday’s paper. The Mexico City rivers in question are covered over by highways and choked by sewage and trash. The architects’ plan is to remove the highways, clean the water, and build parks, meadows, and trails—so desperately needed in that smothering city of 25 million. “It’s urban surgery. It’s not acupuncture,” said the project’s lead architect, Elías Cattan.
Naturally, after reading about their dream—the writer Cave is suitably circumspect about the potential reality of the proposal—I asked Adam Levine if such a thing might be possible in Philadelphia. Adam is the Water Department archivist and the expert in the history of Philadelphia’s physical transformation from a hilly landscape of marsh, pond, stream, and meadow to rowhouse jungle. His wonderfully informative website is PhillyH2O.org. Adam explains that unlike in Mexico City, where the rivers still exist—they are just covered over by infrastructure—in Philadelphia most of the lost creeks are buried in culverts and turned into sewers. Thus, he says:
To try to reclaim these streams would be hugely and, in my opinion, prohibitively expensive, as well as ultimately futile, if the goal is to create a viable stream in an attractive landscape in an urban neighborhood. In combined sewer areas, stream restoration would first involve building a new sewage-only pipe and then re-connecting all the buildings to that pipe. If that was done, and the fill (ranging from 15 to 50 feet deep) was removed from on top of the pipe, the result would be a stream flowing in a deep trench many feet below the street. To recreate the contours of the original valleys though which the streams once ran, thousands of buildings built on filled land in those valleys would have to be razed and all that fill removed as well.
Unnecessary urban surgery indeed. However, a bit of acupuncture could work in certain places. Levine says in places where original streams were placed in culverts but not combined with sewers, the culvert could be removed, especially possible if the creek is in an existing city park. One such place is the Indian Creek, under Morris Park, at 69th and Haverford. “In such areas,” he says, “where streams run under parkland, the original contours could more easily be reconfigured, few if any buildings would have to be demolished in the process, and no new pipes would need to be built.”
Thumbnail graph from Taller 13 Regenerative Architecture via the New York Times